/Engine/Source/Editor/MovieSceneTools/Public/MovieSceneEventCustomization.h
The output array of pin candidates should be of the same size as GetWellKnownParameterPinNames, with an empty array of candidates for those parameters that currently have no compatible pins.
virtual void GetWellKnownParameterCandidates ( [UK2Node](API\Editor\BlueprintGraph\UK2Node) * Endpoint, [TArray](API\Runtime\Core\Containers\TArray)< [FWellKnownParameterCandidates](API\Editor\MovieSceneTools\FMovieSceneDirectorBlueprintEndp-_1\FWellKnownParame-) > & OutCandidates ) const